Change language

Python | Summation of nonzero groups

| | |

Method # 1: Using Loops

This task can be accomplished using the brute force method using loops. We simply loop through each element of the list to check that its subsequent element has a non-zero value, and perform the summation as soon as we find the next value equal to zero, and add it to the list of results.

# Python3 demo code
# sum non-zero groups
# Using loops

 
# initializing list

test_list = [ 4 , 9 , 0 , 0 , 3 , 4 , 5 , 0 , 0 , 4 , 0 ]

 
# printing the original list

print ( "The original list: " + str (test_list))

 
# using loops
# sum non-zero groups

res = []

va l = 0

for ele in test_list:

if ele = = 0 :

if val! = 0 :

res.append (val)

  val = 0

else :

  val + = ele

 
# print result

print ( "The non-zero group summation of list is: " + str (res))

Output:

 The original list: [4, 9, 0 , 0, 3, 4, 5, 0, 0, 4, 0] The non-zero group summation of list is: [13, 12, 4] 

Method No. 2: Using itertools.groupby () + sum ()

This particular task can also be done using the groupby function to group all non-zero values, and the sum function can be used to summarize them.

# Python3 demo code
# summing non-zero groups
# Using itertools.groupby () + sum ()

from itertools import groupby

 
# initializing list

test_list = [ 4 , 9 , 0 , 0 , 3 , 4 , 5 , 0 , 0 , 4 , 0 ]

 
# print the original list

print ( "The original list: " + str (test_list))

 
# using itertools.groupby () + sum ()
# sum non-zero groups

res = [ sum (val) for keys, v al in groupby (test_list,

key = lambda x: x! = 0 ) if keys! = 0 ]

 
# print result

print ( "The non-zero group summation of list is: " + str (res))

Output:

 The original list: [ 4, 9, 0, 0, 3, 4, 5, 0, 0, 4, 0] The non-zero group summation of list is: [13, 12, 4] 

Shop

Learn programming in R: courses

$

Best Python online courses for 2022

$

Best laptop for Fortnite

$

Best laptop for Excel

$

Best laptop for Solidworks

$

Best laptop for Roblox

$

Best computer for crypto mining

$

Best laptop for Sims 4

$

Latest questions

NUMPYNUMPY

Common xlabel/ylabel for matplotlib subplots

12 answers

NUMPYNUMPY

How to specify multiple return types using type-hints

12 answers

NUMPYNUMPY

Why do I get "Pickle - EOFError: Ran out of input" reading an empty file?

12 answers

NUMPYNUMPY

Flake8: Ignore specific warning for entire file

12 answers

NUMPYNUMPY

glob exclude pattern

12 answers

NUMPYNUMPY

How to avoid HTTP error 429 (Too Many Requests) python

12 answers

NUMPYNUMPY

Python CSV error: line contains NULL byte

12 answers

NUMPYNUMPY

csv.Error: iterator should return strings, not bytes

12 answers

News


Wiki

Python | How to copy data from one Excel sheet to another

Common xlabel/ylabel for matplotlib subplots

Check if one list is a subset of another in Python

sin

How to specify multiple return types using type-hints

exp

Printing words vertically in Python

exp

Python Extract words from a given string

Cyclic redundancy check in Python

Finding mean, median, mode in Python without libraries

cos

Python add suffix / add prefix to strings in a list

Why do I get "Pickle - EOFError: Ran out of input" reading an empty file?

Python - Move item to the end of the list

Python - Print list vertically